Endocrine Abstracts

Introduction: There is a lack of epidemiological data on the distribution of haptoglobin and C677T of MTHFR polymorphisms in Caucasians type 2 diabetic patients. The contribution of these two genetic factors to hyperhomocysteinemia and hypercysteinemia can be useful to prevent cardiovascular events and to reduce public health costs. The aim of this study is to evaluate the contribution of haptoglobin and C677T polymorphisms for hyperhomocysteinemia and hypercysteinemia in Portuguese type 2 diabetic patients with and without angiopathy.

Methods: A population-based case–control study in 150 Portuguese type 2 diabetic patients was performed. The study population: group I – 75 patients with angiopathy and group II – 75 patients without angiopathy. Homocysteine and cysteine plasma levels were obtained by validated HPLC methods. The haptoglobin polymorphism was identified by PAGE and peroxidase staining and C677T MTHFR polymorphism by PCR and RFLP. Statistical analysis was performed by odd ratio calculation and linear regression model.

Results: The Hp 2-1 was the most prevalent. The CT and TT genotypes were more frequent in group I (46.4%; 7.2%) than in group II (41.5%; 6.2%). The diabetic patients of group I with the genotypes Hp 2-1 or Hp 2-2 had a higher probability to have hyperhomocysteinemia (OR: 4.19; P=0.021) and hypercysteinemia (OR: 4.55; P=0.028) than diabetic patients from group II. The presence of 677TT and C677T genotypes in group I increased in five times (OR: 5.37; P=0.040) the probability to have hyperhomocysteinemia compared to group II. The association between haptoglobin and C677T polymorphisms increased the probability (OR: 4.14; P=0.004) of having hypercysteinemia in group I.

Conclusion: The haptoglobin and C677T of MTHFR polymorphisms are associated with a predisposition to hyperhomocysteinemia and can be considered genetic risk factors in angiopathy development of Caucasians type 2 diabetic patients.

Disclosure: A Valente acknowledges the financial support and this study were financially supported by the research project PIC/IC/82957/2007 from Fundação para a Ciência e Tecnologia and by Instituto Nacional de Saúde Doutor Ricardo Jorge, I.P.